Determination of Nanocrystal Sizes:  A Comparison of TEM, SAXS, and XRD Studies of Highly Monodisperse CoPt3 Particles

• Published in: Langmuir Vol. 21; no. 5; pp. 1931 - 1936
• Main Authors: Borchert, Holger, Shevchenko, Elena V, Robert, Aymeric, Mekis, Ivo, Kornowski, Andreas, Grübel, Gerhard, Weller, Horst
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.03.2005
• Subjects: Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Particle size; Nanoparticle; Check; Transition metal; Reflection; Small angle X ray scattering; Cobalt; X ray diffraction; Powder; Transmission electron microscopy; Investigation method; Platinum; Monodispersed particle; Diameter; Comparative study; Nanocrystal
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la0477183

One of the most fundamental tasks in nanoscience is the accurate determination of particle sizes. Various methods have been developed to elucidate the mean particle diameter and the standard deviation for an ensemble of nanocrystals. However, good agreement between the results from different methods is not always encountered in the literature. In this study, we investigate colloidally prepared, highly monodisperse CoPt3 nanoparticles by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and powder X-ray diffraction (XRD). The results are compared in order to examine to which extent agreement is obtained by the different techniques when applied to small nanocrystals in the size range below 10 nm. In particular, the applicability of the simple Scherrer formula for size determination from the broadening of XRD reflections is checked. When the different techniques are correctly applied, the results from all methods are in good agreement.